In general, a multi-tubular catalytic reactor in the form of a heat exchanger is one of reactors capable of effectively removing heat derived from chemical reaction. In the multi-tubular catalytic reactor, solid catalysts are filled in a plurality of reaction tubes and reaction gas is fed into the reaction tubes, thereby generating chemical reaction in order to obtain desired products. In addition, a heating medium is circulated through a reactor shell such that the chemical reaction can be optimized.
However, according to the above multi-tubular catalytic reactor, hot spots may locally occur at the reaction tubes, thereby degrading the quality of the catalyst. Accordingly, the life time of the catalyst may be shortened and the yield of a target product may be reduced. In order to solve the above problems, there have been suggested various methods for reducing the hot spots by effectively transferring heat to the reaction tubes installed in the reactor.
For instance, Korean Unexamined Patent Publication No. 2001-50267 discloses a multi-tubular reactor including a heating medium circulation device as well as donut-type baffle plates and disc-type baffle plates, which are provided in a shell, in which the speed of a heating medium is constantly maintained at a predetermined inner region of the reactor, thereby improving the heat transfer efficiency. In addition, in order to uniformly feed (or discharge) the heating medium, which is introduced (or discharged) through one duct, into (or from) the reactor in the circumferential direction of the reactor, openings, such as slits, are intermittently aligned along a circumferential portion of a slit layer of an annular-type distributor. Thus, the heating medium is uniformly fed (or discharged) into (or from) the reactor in the circumferential direction of the reactor through the annular-type distributor having the above structure, thereby reducing the hot spot temperature of the reaction tubes. In addition, in order to allow the heating medium to uniformly flow, the annular-type distributor has a plurality of opening arrays, in which the number and size of openings are adjustable.